Developmental validation of a point-of-care, salivary α-amylase biosensor

Abstract

The translation of salivary alpha-amylase (sAA) to the ambulatory assessment of stress hinges on the development of technologies capable of speedy and accurate reporting of sAA levels. Here, we describe the developmental validation and usability testing of a point-of-care, colorimetric, sAA biosensor. A disposable test strip allows for streamlined sample collection and a corresponding hand-held reader with integrated analytic capabilities permits rapid analysis and reporting of sAA levels. Bioanalytical validation utilizing saliva samples from 20 normal subjects indicates that, within the biosensor’s linear range (10–230 U/ml), its accuracy (R2 = 0.989), precision (CV < 9%), and measurement repeatability (range −3.1% to + 3.1%) approach more elaborate laboratory-based, clinical analyzers. The truncated sampling-reporting cycle (< 1 minute) and the excellent performance characteristics of the biosensor has the potential to take sAA analysis out of the realm of dedicated, centralized laboratories and facilitate future sAA biomarker qualification studies.

Performance Evaluation of a Salivary Amylase Biosensor for Stress Assessment in Military Field Research

“…In our study, we encountered more failures and inconsistencies as compared to those reported in the literature (15,18). These failures could have been in the methods used to collect the samples.…”

Measurement of functional task difficulty during motor learning: What level of difficulty corresponds to the optimal challenge point?

“…Within the biosensor's linear range (10-230 U/ml), the accuracy (R 2 = .989), the precision established by inter-run measurements of saliva samples taken with the same device (the coefficient of variation < 9%), and measurement repeatability (range À3.1% to +3.1%) of this type of handheld monitor has been found to approach that of more elaborate laboratory-based automated clinical chemistry analysis tools (Olympus America Inc., Center Valley, PA, USA) (Shetty, Zigler, Robles, Elashoff, & Yamaguchi, 2011). Salivary a-amylase was measured from saliva samples collected under the tongue by inserting the reagent test strip directly into the subject's oral cavity.…”

Hand-Held Reader for Colorimetric Sensor Arrays

“…18,19,48,49 These methods use only single-point measurements (vs continuous monitoring) and usually require significant operator input, e.g., manual dipstick testing or downloading and manual processing of collected data on a separate computer.…”